Method of and apparatus for changing rolls in a rolling mill



A. .1. BECK 3,443,410 METHOD OF AND APPARATUS FOR CHANGING ROLLS IN A ROLLING MILL May 13, 1969 m m L m hw M m mm m 5 w- 4 M Kw /& m

Filed Aug. 16, 1966 y 3, 1969 A. J. BECK 3,443,410

METHOD OF AND APPARATUS FOR CHANGING ROLLS IN A ROLLING MILL Filed Aug. 16, 1966 Sheet 2 of 2 INVENTOR. 4. J. BECK United States Patent 3,443,410 METHOD OF AND APPARATUS FOR CHANGING ROLLS IN A ROLLING MILL Andrew J. Beck, Cheshire, C0nn., assignor to Textron, Inc., Providence, R.I., a corporation of Rhode Island Filed Aug. 16, 1966, Ser. No. 572,780

Int. Cl. B21b 31/08 U.S. Cl. 72-239 11 Claims ABSTRACT OF THE DISCLOSURE There is provided a method of and apparatus for changing at least one of a pair of cooperating work rolls in a rolling mill so as to clear the work in the pass line between the rolls so that passage of the work in this line is not interrupted during removal of the first-mentioned one of the rolls, which includes pivoting of one of the rolls during roll changing to effect the aforementioned clearance. The apparatus includes means to move this roll on its pivotal axis, and means to remove the firstmentioned roll from the mill on supporting means.

This invention relates to a method of and apparatus for changing rolls in a rolling mill, and relates more particularly to a rolling mill having as a part thereof means for quickly and efficiently changing the rolls when they become worn or their work surfaces or otherwise adversely affected without interruption of the passage of material in the so-called pass line of a rolling operation of material such as steel, for example. In accordance with the invention, the aforementioned rolling operation may employ a plurality of such rolling mills arranged in tandem or may employ a single rolling mill and, if desired, the rolls may be changed by remote control.

p In the rolling of strip steel, for example, for the purpose of reducing the thickness of the material, it has been found necessary by some to change the rolls of a mill for dressing of the work surfaces thereof at short intervals of operation of a rolling mill in such a process. Hence it is important in a mill to reduce to the minimum the down time of each rolling mill employed in the manner previously indicated, that is, for changing rolls. It is believed that heretofore it has been necessary in changing rolls of a mill to remove the material from the pass line between cooperating rolls before changing of the rolls of a mill. This is not necessary in accordance with the present invention and, in fact the passage of material may be continued during roll changing which makes the rolling mill highly suitable for a continuous process such as a galvanizing process, for example, in which the strip of material may be tempered by the mill prior to the galvanizing station in an uninterrupted manner, which material continues to pass through the mill even during roll changing.

One object of the invention is to provide an improved rolling mill well suited to rolling metallic material such as steel but believed not to be limited to rolling metallic material. Another object is to provide a rolling mill with means by which rolls of the mill may be changed very quickly and efficiently, which is well suited to a Z High stand of rolls but which is not limited thereto.

A further object of the invention is to provide such roll-changing means which does not require the use of a turntable, which permits new rolls or reground rolls, that is, rolls which had become worn or affected in other ways by the material worked upon and then were resurfaced or dressed, to be inserted into the mill stand from one side thereof and ejected from the same side, the rolls being insertable into and ejected from each side of the stand but in an alternate fashion.

3,443,410 Patented May 13, 1969 It is also contemplated that the roll-changing means accommodate two cooperating rolls simultaneously. It may withdraw two rolls from a mill stand while simultaneously inserting two new cooperating rolls into the stand and, as previously indicated, the rolls of the mill may be changed without affecting the passage of the material in the so-called pass line of the mill. Furthermore, it is contemplated that in no event should it be necessary to actually remove the material from the pass line of the mill.

'It is a still further object of the invention to provide an improved method of changing rolls in a rolling mill in the manner described above. Further objects will be apparent to those versed in the art from the following detailed description of one form of the method and one embodiment of the rolling mill.

In the drawings:

FIG. 1 is a broken elevational view illustrating in somewhat diagrammatic form a rolling mill incorporating the invention;

FIG. 2 is an end view of two cooperating work rolls of the mill, omitting bearing chocks and other supports;

FIG. 3 is a sectional view taken on line 33 of FIG. 2;

FIG. 4 is a fragmentary view similar to FIG. 1 illustrating a part of the roll-changing procedure; and

FIG. 5 is a view similar to FIG. 4 illustrating a subsequent part of the procedure.

In the drawings the rolling mill is indicated generally at 10 and is shown in association with a mill floor 1.1. The rolling mill comprises upright windowed frame parts 12 and 16 laterally spaced apart and having their windows in alignment with one another, the frame parts being supported on a common bed 14 which may be recessed in the floor as shown. The frame parts .12 and 13 are interconnected at their upper end portions by a frame part 10a.

The illustrated rolling mill is of the Z-I-Iigh type having (FIG. 1) cooperating work rolls 15 and 16, shown received within the mill, with the necks thereof received in the respective windows of the frame parts 12 and 13. The work in the pass line of the mill extends between the two work rolls as shown in FIG. 2, the work being indicated at 17.

The roll 15 of the mill is the upper or loading roll which resists upward pressure from the work and which carries on its necks bearing chocks 15a and 15b respectively, vertically slidable in the windows of the frame parts 12 and 13. It will be noted that the neck received in the bearing chock 15a extends at its outboard end beyond the chock 15a. The illustrated work surface of the roll 15 cooperates with a similar work surface of the roll 16 by virtue of the weight of the roll 15 or the last-mentioned roll may be loaded by conventional loading devices, not shown. The roll 16 is a lower or bearing roll having similar roll necks disposed in similar manner receiving similar bearing chocks r1611 and 16b received in the respective windows of the frame parts 12 and 13, from which the choc-ks 15a and 1512 are supported, respectively, the roll neck received in the bearin hock 16a extending at its outboard end beyond the bearing chock 16a.

The roll 16 is supported through its bearing chocks on approximately one half of an elongated roll sled 18 received in the windowed frame parts 12 and13 on a guideway and there is provided a supporting track 19 on which the sled, equipped with wheels 20, is axially movable. The track 19 extends to either side of the windowed mill stand comprising the frame parts, as shown in FIG. 1. The sled may cooperate with the guideway in any conventional manner fro guiding movement of the former.

The construction and arrangement of the sled and guideway is such that the sled 18, which may extend beyond the mill stand in all of its positions, may be pro jected from either frame part in the manner indicated in the drawings. In FIG. 1 the sled is shown in full lines projecting from the frame part 13 and is shown in phantom projected from the frame part 12.

In the form shown by way of example, the sled is moved by means of a fixed fluid cylinder 21, recessed in the floor, having suitable fluid pressure and relief connections, not shown, at each end so that the pistonequipped rod 22 associated with the cylinder may be reciprocated therein. The outer end of the rod is rigidly connected to the sled 18 as at one end thereof by a suitable plate 23 fixed to the sled in a depending manner and fixed to the outer end of the rod as by having a threaded portion of the latter projecting through the plate 23 and receiving suitable nuts and washers bearing on the plate 23 at each side thereof.

Interposed between the roll chocks a and 16a is a spreader or fulcrum block 24 constructed and arranged to permit the roll 15 with its chocks to pivot thereon on a horizontal axis to the position shown in FIG. 4, while permitting the working face of the roll 15 to cooperate with the working face of the roll 16 in close proximity thereto while the work runs through the mill in the normal positions of the work rolls 15 and 16 shown in full lines in FIG. 1. To support the bearing chock 15b from the bearing chock 16b when the roll 15 is in its working position, a shim 24a may be interposed between the lastmentioned chocks so that the axis of the roll 15 in its working position may be in parallelism with the axis of the roll 16 or, if desired, the chock 15b may have integral therewith a. depending portion to rest on the chock 16b.

In the illustrated form of the invention, the outboard end portions of the roll necks received in the bearing chocks 15a and 16a are provided (FIGS. 2 and 3) with annular grooves 150 and 16c respectively, the grooves being in vertical alignment with one another. These grooves receive a harness common to both rolls for the purpose of pivoting the rolls relatively to one another during the changing of rolls in the mill stand as will be set forth in detail hereinafter, the harness being indicated generally at 25. It is believed that the particular means employed to pivot the roll 15 to the position shown in FIG. 4 is not critical. However, the harness 25 is considered eflicient and useful for this purpose. It consists of a length of wire rope 26 received in the grooves 150 and 16c in the roll necks as best shown in FIGS. 2 and 3. One end of the rope 26 is fixed to the distal end of a piston rod 27 of a fluid cylinder 28 and the other end of the rope is fixed to the cylinder 28, the arrangement being such that the loop around the roll necks effected by the wire rope and the fluid cylinder means is lengthened or the piston rod 27 is extended and shortened when the piston rod is retracted in the cylinder 28. The fluid cylinder is provided with suitable fluid pressure and relief means at either end thereof, not shown.

It will be understood from the foregoing that when the 'harness is rendered operative by fluid pressure in a manner to shorten the loop around the roll necks, the roll 15 is pivoted upwardly (FIG. 4) on fulcrum block 24 by a force which is in effect a squeezing force on the lastmentioned roll necks. It is preferable to apply the squeezing force to the outboard ends of the rolls rather than the bearing chocks 15a and 16a to obtain greater leverage on the roll 15. However, if desired, the force could be applied between the bearing chocks, which is obvious. When the length of the loop of the harness is increased, the roll 15 may assume the full-line position thereof shown in FIG. 1, in which the roll is in parallelism with the cooperating roll 16 in the mill stand. Any tendency of the roll 16 to tip upwardly when the harness is operated to pivot the roll 15 upwardly may be resisted by loading, not shown, the bearing chock 16b by any suitable means.

The operation, that is, with respect to changing rolls in units of two roll, for example, such as the cooperating rolls 15 and 16, will now be briefly explained in connection with a 2-High rolling mill. With reference to FIG. 1, it will be noted that the sled 18 carries, in addition to the rolls 15 and 16, replacement rolls 31 and 32 beyond the frame part 13. The sled 18 supports the work rolls 15 and 16 for operation in the mill stand. When it is desired to change the rolls 15 and 16, the harness 25 is operated to pivot the roll 15 upwardly to the position of FIG. 4, thereby clearing the work between the rolls and permitting the work to free itself from the lower roll 16. If the shim 24a is used, it is removed. In the illustrated form of the rolling mill the work rolls 15 and 16, during their operation in the mill stand, are not driving rolls but are driven by the work.

The rolls 31 and 32 together with their hearing chocks and harness 29 may be identical to those previously described, and the harness 29 may be operated simultaneously with the harness 25 to pivot the roll 31 upwardly to the position shown in the last-mentioned view, the pivoting action taking place on the spreader or fulcrum block 30 like the block 24, interposed between the bearing chocks of the rolls 31 and 32 nearest the harness 29. The fluid cylinder 21 is then operated in a manner to retract the piston rod 22 to the extent necessary to roll the sled 18 on its wheels in a direction and a suflicient distance to remove the rolls -15 and 16 from the frame parts 12 and 13 of the mill stand to the position shown in phantom in FIG. 1, while simultaneously moving the rolls 31 and 32 and their associated parts, as indicated in FIG. 5, into the windowed frames 12 and 13 so that they occupy the transverse positions in the mill stand formerly occupied by the rolls 15 and 16.

It will be noted that the roll units, each comprising a pair of rolls, are arranged on the sled in a manner such that the harness and associated roll necks of each unit are outermost on the sled 18, that is, outermost with reference to the length of the sled. If the work rolls are provided with backup rolls, not shown, or if loading devices are employed in the mill stand, it will be understood that these must first be moved a suflicient distance to permit pivoting of the upper work roll of the roll unit which is being replaced to the position shown in FIG. 4.

When the rolls 15 and 16 are removed from the mill stand on the sled 18 and the replacement mill rolls 31 and 32 drawn into the stand on the sled, all by movement of the sled 18 to the left as viewed in FIG. 1, the rolls 15 and 16 and their associated bearing chocks occupy the positions shown in phantom in FIG. 1. The harnesses are then operated in the above-described manner to lower the pivotal roll 15 to a position in parallelism with the roll 16 wherein the bearing chock 15b is supported from the bearing chock 16b.

Simultaneously with the pivoting movement of the roll 15 to move it downwardly, pivoting movement of the roll 31 may take place through operation of the harness 29 so that the roll 31 is positioned in the mill stand with its axis parallel to the axis of roll 32 with the bearing chocks of the roll 32 supporting the bearing chocks of the roll 31. It will be appreciated that as the roll 31 is moved in this manner, the work is engaged between the rolls 31, 32. This change of rolls may take place quickly.

A crane may then be employed to remove the roll unit consisting of the rolls 15 and 16 and their associated parts from the sled 18, after which a new roll unit may be placed on the sled in the same longitudinal position thereon formerly occupied by the rolls 15 and 16. As previously indicated, the roll unit is placed on the sled with the harness and associated roll necks outermost on the sled. When the rolls 31, 32 require replacement, the passage of the work material through the mill stand need not be interrupted. The roll 31 is pivoted upwardly by operation of the harness 29 so that the work is freed, while the uppermost roll of the replacement unit is moved in a similar manner and the sled 18 is then moved to the right, as viewed in FIG. 1, to inject replacement rolls into the mill stand and eject the rolls 31 and 32.

The method of the invention may be carried out by apparatuses of various types as previously indicated. Briefly the method may be explained as comprising the step of pivoting the upper of two work rolls in a stand upwardly on a fixed axis to clear the work intermediate the work rolls without interrupting the passage of the work through the mill stand and withdrawing the upper and lower rolls from the mill stand from the same side of the mill stand from which they were previously injected into the stand, and injecting into the stand from the other side thereof a roll unit comprising cooperating upper and lower rolls while the upper roll is maintained in a pivoted position relatively to the lower roll to clear the work as it enters the stand, and subsequently lowering the last-mentioned upper roll on its pivotal axis so that it may cooperate with the lower roll in the mill stand and engage the work, and lowering the upper roll of the firstmentioned roll unit in parallelism with the lower roll of the last-mentioned unit for removal of the last-mentioned unit from proximity to the mill stand as for dressing of the work surfaces of the rolls thereof.

While only one form of the apparatus and method has been illustrated in the drawings and described above, it will be apparent to those versed in the art that the invention may take other forms and is susceptible of various changes in details without departing from the principles of the invention and the scope of the appended claims.

I claim:

1. In apparatus for changing rolls of a rolling mill having a windowed stand receiving therein a pair of cooperating work rolls including bearing chocks on the respective rolls necks, provided with support means to enable at least one of the work rolls to be moved into and out of the windowed stand, the improvement of means pivoting one of the work rolls at one end portion thereof relatively to the support means to swing on an axis transverse to the axis of the other work roll, carrying with it the chock at the other end portion of the pivotal roll so that it may pivot away and be completely free from the corresponding chock of said other roll, to clear the work in the pass line between the rolls so that passage of the work in this line is not interrupted during removal of the first-mentioned one of the rolls, means to inject and eject the first-mentioned one of the rolls from the mill stand on the supporting means, and means to move said pivotal roll with its last-mentioned chock toward and away from the other roll on the aforesaid pivotal axis.

2. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the pivot of said one roll is arranged intermediate the other bearing chock thereof and said support means.

3. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the pivot of said one roll is between the other bearing chock of the last-mentioned roll and the corresponding bearing chock of the other roll.

4. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the pivot of said one roll is in the form of a fulcrum block between the other bearing chock of the last-mentioned roll and the corresponding bearing chock of the other roll and the last-mentioned roll is removable with said one roll on the supporting means.

5. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein said means for moving said one roll on the pivotal axis thereof comprises a length of wire rope looped around two corresponding extensions of the roll necks beyond the pivot of said one roll and seated on said extensions and a fluid cylinder having the body thereof connected to one end of the rope and having an extensible piston rod connected to the other end of the rope.

6. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the means to move said one roll on the pivotal axis thereof comprises an extension of corresponding roll necks of the rolls in one direction beyond the pivot of said one roll and a mechanism interconnecting the last-mentioned roll necks to exert a force thereon, moving them relatively toward one another.

7. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the pivot of said one roll is between the other bearing chock of the last-mentioned roll and the corresponding bearing chock of the other roll, and said other roll is removable with said one roll on the supporting means, the means for supporting the pair of rolls also supporting a replacement pair of rolls in axial alignment with the respective first-mentioned rolls and having bearing chocks therefor, and means to pivot one replacement roll relatively to the other to swing away from the other carrying with it one of the bearing chocks on the distal end portion thereof so that the last-mentioned chock may be completely free from its neighbor to clear the work when said replacement rolls are injected into the mill stand on ejection of the first-mentioned pair of rolls from the stand, and means to move said one of the replacement rolls with its last-mentioned chock toward and away from the other replacement roll on the aforesaid pivotal axis.

8. Apparatus for changing rolls of a rolling mill as defined in claim 1, wherein the roll which is injected and ejected from the mill stand on the supporting means is said other roll which cooperates with the pivotal roll.

9. Apparatus for changing rolls of a rolling mill as defined in claim 4 wherein the means to pivotally move said one roll comprises an extension of corresponding roll necks of the rolls in one direction beyond the pivot of said one roll and a mechanism interconnecting the lastmentioned roll necks to exert a force thereon, moving them relatively toward one another.

10. Apparatus for changing rolls of a rolling mill as defined in claim 5, wherein the pivot of said one roll is in the form of a fulcrum block between the other bearing chock of the last-mentioned roll and the corresponding bearing chock of the other roll, and said other roll is removable with said one roll on the supporting means.

11. In a method for changing a pair of work rolls in a rolling mill having a pass line for the work between the rolls and a windowed'stand receiving therein the rolls including bearing chocks on the respective roll necks, provided with support means to enable the rolls to be moved into and out of the windowed stand, the step of pivoting one work roll of the pair on an axis transverse to the axis of its companion to swing in a direction away from its companion carrying with it the chock at its distal end, so that it may be completely free from the corre sponding chock of the other roll, to clear the work in the pass line between the rolls, and withdrawing the pair of rolls from the windowed stand and inserting in place thereof a second pair of work rolls together with their hearing chocks on a support with one replacement roll and the chock carried on the distal end thereof pivoted to a position similar to the pivoted position of said pivoting roll of the first pair but reversed with respect thereto in the mill stand, to clear the pass line so that the passage of the work in this line is not interrupted during the changing of rolls.

References Cited UNITED STATES PATENTS 749,745 l/ 1904 Von Philp 72-239 3,190,099 6/1965 Sieger et al. 72238 3,221,530 12/1965 Swallow et a1. 72-239 3,309,909 3/ 1967 Wilson 7224O CHARLES W. LANHAM, Primary Examiner. B. J. MUSTAIKIS, Assistant Examiner. 

